A PDF document is suppose to be platform independent, however that is not always the case. A lot of times when a PDF is created fonts are not embedded in the document and will be operating system dependent. While submitting PDFs to IEEE this can be an issue.
Checking if the fonts are embedded
Embedding Fonts
<install path>/gs<version number>/bin
.gsWin32 -dSAFER -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sPAPERSIZE=a4 -dPDFSETTINGS=/printer -dCompatibilityLevel=1.3 -dMaxSubsetPct=100 -dSubsetFonts=true -dEmbedAllFonts=true -sOutputFile=d:\Output_filename.pdf Input_filename.ps
Remember to change the input and the output filename. Also, if the script is not able to write the output file due to access restrictions(typically on C:\ and C:\ProgramFiles ) it would not give an error.
Source for the script : http://www.hamilton.ie/gavinmc/docs/timesinpdfs.html